t25 2.1 wbx overheating

[bigdubber]

renewed head gaskets and piston sleeve seals green and black.
flushed out radiator. bled system.
heater matrix blows hot air but radiator stays cold.
engine gets pretty hot. temp sender shows below half. no red light flashing .
replaced black cap on expension tank for blue cap.
water sprays out of bleed nut on radiator.
after 30 mins of ticking over and reving the engine .radiator still cold.
checking the 2 steel pipes on back of engine .bottom pipe hot top pipe cold.
rev the engine and the top pipe warms up and bottom half of the radiator gets hot.
also check the 2 main pipes running to radiator.
one is hot one is cold.
new thermostat fitted aswell

[Aidan]

below 1/2 the tstat hasn't opened, but it should have got to full temp and cycling the rad fan by 30 mins, mine comes up to temp is 15 mins at idle, i'd say the tstat is no good or there's a blockage somewhere on the system to and fro the rad - I once had the inner reinforcement of a plastic pipe break up and travel up the pipe to a bend and act as a valve, but that was on a diesel
what happens if you drive it ?

[..lee..]

engine gets pretty hot. temp sender shows below half. no red light flashing .

you sure its overheating.

[kevtherev]

WBX rads are plumbed different to normal



One question;
How old is the radiator?
Original?
here's how it works.. like I said they are not like normal rads

[jason k]

what stat? gsf or a proper vw one?

if gsf, change it for a proper one

[bigdubber]

the stat was from just campers.
the radiator is the original one . have removed it and flushed it out.
the engine gets red hot . the air coming from the heater matrix is roasting.
and the rad gets hot in patches on the bottom half after at least 45 mins +.

[kevtherev]

the stat was from just campers.
the radiator is the original one . have removed it and flushed it out.
the engine gets red hot . the air coming from the heater matrix is roasting.
and the rad gets hot in patches on the bottom half after at least 45 mins +.

well that sounds about right, but I doubt your engine is red hot. after 45 mins it should be at 87 deg c wich is not red hot but scalding

[bigdubber]

the engine gets red hot to the touch.
it could just be me over reacting.
but it did go off like a kettle the day before.
havnt took it for a proper run as of yet.
just thought it strange that the 2 metal pipes that run over the engine. the bottom one was very hot and the top one stone cold.

[Aidan]

2 metal pipes over the engine ? are we talking syncro ?

[bigdubber]

yes its a syncro crewcab

[Aidan]

top pipe is send to rad only gets hot once the thermostat opens

[bigdubber]

bottom pipe gets very hot top pipe cold

[Aidan]

tstat not working then or you've connected the rad pipes back to front
good tstat from brickwerks

[bigdubber]

bottom of the rad gets hot after a while and top stays cold. still same with rear pipes .
in spain at the mo so will have to try local vw dealer for stat
cheers

[kevtherev]

I think you have a radiator blockage mate.
you do have the stat in the right way round as well yes?